glCompressedTexSubImage1D

specify a one-dimensional texture subimage in a compressed format

Signature

glCompressedTexSubImage1D( GLenum ( target ) , GLint ( level ) , GLint ( xoffset ) , GLsizei ( width ) , GLenum ( format ) , GLsizei ( imageSize ) , const void * ( data ) )-> void
glCompressedTexSubImage1D( target , level , xoffset , width , format , data )
glCompressedTextureSubImage1D( GLuint ( texture ) , GLint ( level ) , GLint ( xoffset ) , GLsizei ( width ) , GLenum ( format ) , GLsizei ( imageSize ) , const void *( data ) )-> void
glCompressedTextureSubImage1D( texture , level , xoffset , width , format , imageSize , data )

Parameters

VariablesDescription
target
Specifies the target, to which the texture is bound, for glCompressedTexSubImage1D function. Must be GL_TEXTURE_1D .
texture
Specifies the texture object name for glCompressedTextureSubImage1D function.
level
Specifies the level-of-detail number. Level 0 is the base image level. Level n is the n th mipmap reduction image.
xoffset
Specifies a texel offset in the x direction within the texture array.
width
Specifies the width of the texture subimage.
format
Specifies the format of the compressed image data stored at address data .
imageSize
Specifies the number of unsigned bytes of image data starting at the address specified by data .
data
Specifies a pointer to the compressed image data in memory.

Description

Texturing allows elements of an image array to be read by shaders.
glCompressedTexSubImage1D and glCompressedTextureSubImage1D redefine a contiguous subregion of an existing one-dimensional texture image. The texels referenced by data replace the portion of the existing texture array with x indices xoffset and xoffset + width - 1 , inclusive. This region may not include any texels outside the range of the texture array as it was originally specified. It is not an error to specify a subtexture with width of 0, but such a specification has no effect.
internalformat must be a known compressed image format (such as GL_RGTC ) or an extension-specified compressed-texture format. The format of the compressed texture image is selected by the GL implementation that compressed it (see glTexImage1D ), and should be queried at the time the texture was compressed with glGetTexLevelParameter .
If a non-zero named buffer object is bound to the GL_PIXEL_UNPACK_BUFFER target (see glBindBuffer ) while a texture image is specified, data is treated as a byte offset into the buffer object's data store.

Errors

GL_INVALID_ENUM is generated if internalformat is not one of the generic compressed internal formats: GL_COMPRESSED_RED , GL_COMPRESSED_RG , GL_COMPRESSED_RGB , GL_COMPRESSED_RGBA . GL_COMPRESSED_SRGB , or GL_COMPRESSED_SRGB_ALPHA .
GL_INVALID_VALUE is generated if imageSize is not consistent with the format, dimensions, and contents of the specified compressed image data.
GL_INVALID_OPERATION is generated if parameter combinations are not supported by the specific compressed internal format as specified in the specific texture compression extension.
GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the GL_PIXEL_UNPACK_BUFFER target and the buffer object's data store is currently mapped.
GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the GL_PIXEL_UNPACK_BUFFER target and the data would be unpacked from the buffer object such that the memory reads required would exceed the data store size.
GL_INVALID_OPERATION is generated by glCompressedTextureSubImage1D function if texture is not the name of an existing texture object.
Undefined results, including abnormal program termination, are generated if data is not encoded in a manner consistent with the extension specification defining the internal compression format.

Associated Gets

glGet with argument GL_TEXTURE_COMPRESSED
glGet with argument GL_PIXEL_UNPACK_BUFFER_BINDING
glGetTexLevelParameter with arguments GL_TEXTURE_INTERNAL_FORMAT and GL_TEXTURE_COMPRESSED_IMAGE_SIZE

Version Support

glCompressedTexSubImage1D
glCompressedTextureSubImage1D

See Also

Copyright

Copyright
1991-2006 Silicon Graphics, Inc. Copyright
2010-2014 Khronos Group. This document is licensed under the SGI Free Software B License. For details, see .

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